Pickering Emulsions Stabilized by pH-Responsive Microgels and Their Scalable Transformation to Robust Submicrometer Colloidoisomes with Selective Permeability

• DOI: 10.1021/acs.langmuir.7b01618
• Publication Date: 2017-07-27T18:44:18Z
• Authors: Wenkai Wang; Amir H. Milani; Zhengxing Cui; Mingning Zhu; Brian R. Saunders
• Keywords: Pickering emulsion; Emulsion polymerization

Colloidosomes are micrometer-sized hollow particles that have shells consisting of coagulated or fused colloid particles. While many large colloidosomes with sizes well above 1.0 μm been prepared, there fewer examples submicrometer colloidosomes. Here, we establish a simple emulsion templating-based method for the preparation robust pH-responsive microgel The constructed from based on ethyl acrylate and methacrylic acid peripheral vinyl groups. microgels acted as both Pickering stabilizer macro-cross-linker. formation studies showed minimum droplet diameter was reached when were partially swollen. Microgel prepared by covalently interlinking adsorbed at oil-water interface using thermal free-radical coupling. standard high-shear mixer two different rotor corresponded to high shear (HS) very (VHS) mixing conditions. latter enabled construction microgel-colloidosomes gram scale. swelled strongly pH increased 6.0. no evidence colloidosome breakup pH. effect solute size shell permeation studied range FITC-dextran polymers, size-selective occurred. average pore VHS estimated be between 6.6 9.0 nm 6.2. microgel-colloidosome properties suggest they potential future applications in cosmetics, photonics, delivery.